1886, Robert Brown, Spunyard and Spindrift, A Sailor Boy's Log of a Voyage Out and Home in a China Tea-clipper:

Then the names of all the other things on board a ship! I don't know half of them yet; even the sailors forget at times, and if the exact name of anything they want happens to slip from their memory, they call it a chicken-fixing, or a gadjet, or a timmey-noggy, or a wim-wom—just pro tem., you know.

any device or machine, especially one whose name cannot be recalled. Often either clever or complicated.

He bought a neat new gadget for shredding potatoes.

That's quite a lot of gadgets you have collected. Do you use any of them?